Contact lens containers of various styles and functionality are utilized for storing, cleaning and/or disinfecting contact lenses. In some lens containment and care systems a hydrogen peroxide based lens care solution is used, wherein the contact lenses to be cleaned and/or disinfected are deposited in contact with the hydrogen peroxide solution for a certain period of time, in order that cleaning and/or disinfecting of the contact lenses can take place to a satisfactory extent. During the duration of the cleaning or disinfecting process, the hydrogen peroxide (H2O2) in the lens care solution may be broken down into water (H2O) and oxygen (O2), for example with the aid of catalase tablets which give a delayed release of the catalase which initiates and accelerates the decomposition process, or a catalyst element or disk. The term “catalysts” means any material that catalyses the decomposition of hydrogen peroxide. The catalyst is preferably a solid, and more preferably a metal or metal oxide of transition metal from Periods 3 to 12 of the Periodic Table, or one of the lanthanide elements. Particularly preferred is platinum, more particularly platinum oxide. Different transition metals follow different reaction pathways in the decomposition of hydrogen peroxide. For example, applicants believe the peroxide is decomposed using platinum ion as catalyst following the following mechanism:2H2O2+Ptn+→2H2O+O2+Ptn+.After completion of the decomposition process, cleaning and/or disinfecting is finished and the contact lenses may be removed from the container and inserted into the eye either directly or after treating with a rinsing solution.
The contact lens containers utilized in such lens care systems typically comprise closable baskets, which open to receive the contact lenses to be cleaned and close to retain the lenses during treatment. The baskets are typically part of a contact lens holder component, which in turn can be connected to the cap of a contact lens container. Before the cap is placed onto the container cup, the container cup is dosed to a fill level with a hydrogen peroxide lens care solution. A catalase tablet, which gives delayed release of catalase, can be added to the container cup before or after adding the hydrogen peroxide solution. Finally, the contact lens holder containing the lenses to be treated is immersed into the hydrogen peroxide solution in the container cup, and the container is closed by screwing the cap onto the container cup.
The closure of the cap on the container cup may form a water-tight seal, to prevent leakage of the cleaning solution. The contact lenses are allowed to remain immersed in the solution for a period of time sufficient to complete the specified cleaning and/or disinfecting process. The oxygen produced from decomposition of hydrogen peroxide in the cleaning solution typically must be allowed to discharge from the container in some manner. U.S. Pat. No. 6,945,389, incorporated herein by reference, discloses various known gas discharge mechanisms.
Continued improvements to lens care systems for cleaning, disinfecting and storing contact lenses are desired. It is to the provision of improved lens care systems that the present invention is primarily directed.